DEVELOPMENT OF A NEW DRUG CARRIER MADE FROM ALGINATE

A new approach for the preparation of nanoparticles is presented. The method is based on control of the gelification phenomenon of alginate by calcium ions, and it leads to small particles of a wide range of ve ry well-defined sizes (250-850 nm) depending on the alginate concentra tion. The particles are formed in a sodium alginate solution by additi on of calcium chloride and then poly-L-lysine. The concentrations of s odium alginate and of calcium chloride were lower than those required for gel formation and corresponded to the formation of a pregel state. The size af the particles formed is greatly dependent on the order of addition of calcium and poly-L-lysine to the sodium alginate solution . This phenomenon can be attributed to the difference in the nature of the interactions between calcium and alginate and between poly-L-lysi ne and alginate. Furthermore, the data indicate that the formation of the particles probably occurs during the addition of the first compone nt to the sodium alginate solution. Evaluation of the drug-loading cap acity was done with doxorubicin as a drug model. The results indicate that alginate nanoparticles are interesting carriers because the drug- loading capacity could be > 50 mg of doxorubicin per 100 mg of alginat e.